RMI 368 Electra-Piano and Harpsichord

Rocky Mount Instruments or RMI was a subsidiary of the Allen Organ Company, established in about 1966. It was based in Rocky Mount, North Carolina. It is most famous for the RMI Electra Piano, a keyboard instrument that created piano and harpsichord-like sounds without the use of strings, tines, or reeds, instead using transistors, much like the combo organs of the day.

In fact, the first models produced were combo organs, including the four-octave "Explorer" (using a dedicated oscillator for each key), the "Lark", the "Band Organ" (a three-octave electrical imitation of a calliope) and the "Calliope" and "Calliope B" around 1968 or early 1969. The first electric piano model was the "Model 100 Rock-Si-Chord" in 1967. Retailing for $4,695, it contained only 2 sounds (string and lute) but was later updated as the "Model 100A" which contained 5 sounds (harpsichord, cembalo, lute, Guitar A, and Guitar B). The "Model 200 Rock-Si-Chord" produced in 1968 was similar the first "Model 100", but featured an accenter option that shortened the decay of the sound. The "Model 200A" however featured twice as many sounds as the "Model 100A".

Beginning in 1967, RMI began producing the 300 Series Electra-piano, the sound of which became very familiar to fans of bands such as Genesis (who used the instrument extensively from 1974 to 1977), Yes and Deep Purple. The original 300A and B models had 61 keys. Eventually seven more keys were added to create the 368 model (but not touch-sensitivity).

The 368x was essentially a 368 housed in a new molded plastic case instead of the previously used vinyl covered plywood. In 1973, RMI came out with the Model 400 which was a 300 with a self-contained sound system aimed more at the home-user market, and the 600 series, which was a stereo version of the 300 with two tone generators per key, but also included some newer sounds.

In 1974, RMI produced the pioneering "Keyboard Computer" model keyboard instrument, the first portable digital sample player. It produced sounds from waveform model punch cards which were input and digitized into volatile memory, and used no magnetic tapes (in contrast to how Mellotron, Chamberlin, and Birotron created their sounds).

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